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稀有金属材料与工程 2012年第S1期41卷 57-60页

作者： Wu, G. M. Tu, K. N. Kuo, C. C. Univ Calif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA Chang Gung Univ Inst Electroopt Engn Tao Yuan 333 Taiwan

High quality GaN epitaxy thin films have been desired for the energy-efficient,solid-state semiconductor illuminating devices.Silicon substrates offer high crystal quality,low wafer cost,large wafer size,and potential integration with the well-established silicon processing technologies.However,due to the large mismatch in lattice constants and thermal expansion coefficients,it is still challenging to grow high quality GaN on silicon substrates.In this study,high quality GaN epitaxy has been engineering designed to grow on Si(111)substrate using varying GaN/AlGaN composite buffer structures by an Axitron 200 metal-organic vapor phase epitaxy deposition system.A thin AlN seed layer of 25 nm was firstly grown at 720℃.AlGaN layer of different thickness was then grown at 1050℃with subsequent GaN thin film until the total thickness reached 500 nm.The thickness of the subsequent GaN thin film could be increased by reducing the AlGaN thickness in the composite buffer structures.The results have shown that the lower GaN/AlGaN thickness ratio would decrease the dislocation density and provide crack-free,mirror-like upper GaN crystal thin film.On the other hand,the GaN/AlGaN thickness ratio could be designed to be 2-6 to balance the processing cost and the thin film quality for engineering applications.The dislocation density has been about 2×10 9 cm-2.In addition,dislocation close loop was observed near the GaN/AlGaN interface.The annihilation mechanism could be depicted by the reduction in dislocation strain energy.

关键词： gallium nitride dislocation density silicon substrate buffer layer

Contract theory based incentive mechanism design for buffer resource in wireless caching networks

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High Technology Letters 2020年第2期26卷 152-159页

作者：刘婷婷 Tang Lei Zhu Hao Bao Yongqiang Guo Yajuan School of Information and Communication Engineering Nanjing Institute of TechnologyNanjing 211167P.R.China Institute of Electric Power Science Jiangsu Electric Power Co.Ltd.Nanjing 210024P.R.China

Evidences indicate that,due to the limited caching capacity or inaccurate estimation on users’preferences,the requested files may not be fully cached in the network edge.The transmissions of the un-cached files will also lead to duplicated transmissions on backhaul channels.buffer-aided relay has been proposed to improve the transmission performance of the un-cached files.Because of the limited buffer capacity and the information asymmetric environment,how to allocate the limited buffer capacity and how to incentivize users in participating buffer-aided relay have become critical issues.In this work,an incentive scheme based on the contract theory is proposed.Specifically,the backlog violation probability,i.e.,the buffer overflow probability,is provided based on the martingale theory.Next,based on the backlog violation probability,the utility functions of the relay node and users are constructed.With the purpose to maximize the utility of the relay node,the optimal contract problem is formulated.Then,the feasibility of the contract is also demonstrated,and the optimal solution can be obtained by the interior point method.Finally,numerical results are presented to demonstrate effectiveness of the proposed contract theory scheme.

关键词： contract theory buffer resource allocation wireless caching network incentive mechanism design

On optimal receiver buffer size in adaptive Internet video streaming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 112-118页

作者： OZBEK Nukhet TUNALI E.Turhan International Computer Institute Ege University BornovaIzmir 35100Turkey

The effect of receiver buffer size on perceived video quality of an Internet video streamer application was examined in this work. Several network conditions and several versions of the application are used to gain understanding of the response to varying buffer sizes. Among these conditions local area versus wide area, bandwidth estimation based versus non-bandwidth estimation based cases are examined in detail. A total of 1000 min of video is streamed over Intemet and statistics are collected. It was observed that when bandwidth estimation is possible, choosing larger buffer size for higher available bandwidth yields quality increase in perceived video.

关键词： Video streaming, Receiver buffer size

Room-temperature deposition of yttria-stabilized zirconia buffer layer on metallic substrates by laser ablation

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Chinese Science Bulletin 1997年第16期42卷 1345-1350页

作者： Xiong, XM Zhou, YL Chen, ZH Lu, HB Zhu, AJ Cui, DF Wang, HS Yang, GZ Chinese Acad Sci Inst Phys Lab Opt Phys Beijing 100080 Peoples R China Chinese Acad Sci Ctr Condensed Matter Phys Beijing 100080 Peoples R China

THE preparation of high-temperature superconducting (HTSC) wires or tapes is very important for the power application of HTSC. High-J_c properties of Y-Ba-Cu-O thin film at liq uid-nitrogen temperature are very attractive not only for small-sized electronic devices, but also for large-scale applications such as high-power transmission cables, high-field magnets and large-scale microwave components. Large-current power application would be achieved if high-J_c YBCO films were grown on practical cheap and flexible metallic substrates. An yttria-stabi-

关键词： YSZ low temperature PLD buffer layer metal substrate.

Simulation on Remanufacturing Cost by Considering Quality Grade of Returns and buffer Capacity

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Journal of Shanghai Jiaotong university(Science) 2019年第4期24卷 471-476页

作者：郑玉巧张铖铖苏春 School of Mechanical and Electronic Engineering Lanzhou University of TechnologyLanzhou730050China School of Mechanical Engineering Southeast UniversityNanjing211189China

Selecting the remanufacturing system as object of the study, the buffer capacity is served as control variable, and design of experiment(DOE) and simulation are used to analyze the effect that uncertain quality of returns acts on system performance. The remanufacturing time and the recovery rate in each station are used to represent the quality level of the returns, and the variance of remanufacturing time is used to denote the variability of returns’ quality. Three factors(the variability, the proportion and the recovery rate) of different quality levels in returns are considered. By analyzing the variance and the range of the simulation results, some important conclusions are obtained: recovery rate affects the remanufacturing cost by far, and the variability has the minimum influence;furthermore, for the returns, the more obvious of the dispersion degree, the higher proportion of the high-level quality, and the higher of the recovery rate, the lower the cost of remanufacturing will be.

关键词： remanufacturing buffer simulation design of experiment(DOE) quality grade

Application of the buffer theory for evaluating attenuation and natural remediation of ionic pollutants in aquatic ecosystems

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Ecological Processes 2015年第1期4卷 180-189页

作者： Igor Povar Oxana Spinu Institute of Chemistry of Academy of Sciences of Moldova 3 Academiei str.ChişinăuMD 2028Republic of Moldova

The main focus in this review is showing how to use the developed buffer theory for assessing and predicting the long-term phenomena of attenuation and natural remediation of ionic pollutants in contaminated aquatic ecosystems,as well as for analyzing the way by which metals move and transform within the environment,the distribution of metals in ecosystems,their deposition and cycling in the terrestrial environment.The buffer theory is based on the rigorous thermodynamic analysis of complex chemical equilibria under environmental conditions in aquatic ecosystems,as natural waters and soils.It has been established that both homogeneous and heterogeneous systems manifest a buffer action towards all their components.The buffer properties in relation to the solid phase components are amplified with an increase of solubility due to protolytic or complex formation equilibria in saturated solutions.It has been established that the buffer capacities of components are mutually proportional,whereas for heterogeneous systems these relationships depend on the stoichiometric composition of solid phases.The use of the developed buffer approach may yield extended knowledge and a deeper understanding of the processes that control the concentrations of components.A number of the important conclusions concerning the investigated buffer systems have been made.The obtained results are indented to provide researchers with a tool needed to help them to set reliable limits of ion(metal)levels in the environment.

关键词： buffer capacity Ecosystem Heterogeneous multicomponent system Proportionality relation between buffer capacities

A buffer MODEL PREDICTING THE VARIATION OF pH IN WATERS

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Chinese Science Bulletin 1992年第20期37卷 1700-1703页

作者：刘洪杰 Department of Geography South China Normal University Guangzhou 510631 PRC

Many models about the change of pollutants have been established for the estimating, assessing and planning about water quality. Because of the complicated influential factors, no suitable and convenient model has ever been practised to predict the variation of active acidity in natural waters. The author recently raised a primary and simple method.

关键词： natural water acidity buffer model

Application of Improved Z-buffer Technique to RCS Computation

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 53-55页

作者： Cao Qinfeng, Xu Penggen(College of Electronic Information, Wuhan University, Wuhan 430072, China)

This paper presents a new method for computation of the monostatic radar cross section (RCS) of electrically large conducting objects. Compared with the traditional Z-buffer technique, the improved one can record not only the illuminated surface of the body, but also the information about the shadowed part. So multi-scattering and RCS of cavity can be calculated. The second advantage of it is using dual representation, of the target's facet surface, in which the illuminated part is treated as bicubic patches for RCS calculation, and is simplified to flat facet when ray tracing is done. Excellent agreement with the experiment has been obtained.

关键词： Key words RCS complex target Z buffer EM scattering

Design and implementation of a delay-optimized universal programmable routing circuit for FPGAs

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Journal of Semiconductors 2009年第6期30卷 132-137页

作者：吴方张火文来金梅王元陈利光段磊童家榕 State Key Laboratory of ASIC & System Fudan University

This paper presents a universal field programmable gate array（FPGA） programmable routing circuit,focusing primarily on a delay optimization.Under the precondition of the routing resource＇s flexibility and routability,the number of programmable interconnect points（PIP） is reduced,and a multiplexer（MUX） plus a buffer structure is adopted as the programmable switch.Also,the method of offset lines and the method of complementary hanged end-lines are applied to the TILE routing circuit and the I/O routing circuit,respectively.All of the above features ensure that the whole FPGA chip is highly repeatable,and the signal delay is uniform and predictable over the total chip.Meanwhile,the buffer driver is optimized to decrease the signal delay by up to 5%.The proposed routing circuit is applied to the Fudan programmable device（FDP） FPGA,which has been taped out with an SMIC 0.18-μm logic 1P6M process.The test result shows that the programmable routing resource works correctly,and the signal delay over the chip is highly uniform and predictable.

关键词： FPGA programmable routing resource delay MUX buffer

A DESIGN METHODOLOGY FOR LOW-LEAKAGE AND HIGHPERFORMANCE buffer BASED ON DEVIANT BEHAVIOR OF GATE LEAKAGE

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Journal of Electronics(China) 2014年第5期31卷 411-415页

作者： Yu Le Sun Jiabin Chen Zhujia Wang Zhaoxin Zhang Chao Yang Haigang Institute of Electronics Chinese Academy of Sciences University of Chinese Academy of Sciences

Based on the observation that both subthreshold and gate leakage depend on transistors width, this paper introduces a feasible method to fast estimate leakage current in buffers. In simulating of leakage current with swept transistor width, we found that gate leakage is not always a linear function of the device geometry. Subsequently, this paper presented the theoretical analysis and experimental evidence of this exceptional gate leakage behavior and developed a design methodology to devise a low-leakage and high-performance buffer with no penalty in area using this deviation.

关键词： Subthreshold leakage Gate leakage buffer Inverse Narrow Width Effect(INWE)